John h



(No Model.) 2 Sheets--Sheet 1. J. H. STOKES. MACHINE FOR MAKING RASPS.

No. 521,424. Patented June 12, 1894.

2 Sheets-Sheet 2. J. H. STOKES.

MACHINE FOR MAKING RASPS.

Patented June 12, 1894.

(No Model.)

1 UNITED STATES JOHN H. STOKES,

OF FREEHOLD, NEW JERSEY, ASSIGNOR TO THE STOKES BROS. MANUFACTURING COMPANY, OF SAME PLACE.

MACHINE FOR MAKING RASPS.

SPECIFICATION forming part of Letters Patent No. 521,424, dated June 12, 1894.

A Application filed March 2,1892. Serial No. 423| 0 N0 model) To all whom it may concern:

Be it known that I,-JOHN H. STOKES, a citizen of the United States of America, residing at Freehold, in the county of Monmouth and State of New Jersey, have invented certain new and useful Improvements in Machines for Maklng Rasps, of which the following is a specification.

Heretofore in the manufacture of rasps by machinery it has been found essential to make teeth by raising them from the surface of the blank by means of a pivotally yielding punch, the cutting end of which penetrates the metal at an angle to the face thereof, describing a circle to lift the metalout of the recess formed to make the projecting tooth, and this movement of the point of the punch has been found to be necesssary, for if the punch entered the metal direct at the ordinary angle at which the blank and punch are held relatively to eachother an indentation only in the metal would result. I have found however, by experiment, that by increasing the angle at which the blank is held relatively to the punch and changing the form of the punch as hereinafter explained the punch may have a positive downward movement into the metal of the blank without any forward or pivotal movement of its penetrating end as has been heretofore found necessary; this action making a recess, the walls of which are practicallyat right angles meetmg on a straight line at the bottom of the recess, the teeth formed being in all particulars similar to those heretofore formed by the old process. sult was very satisfactory the means for producing the result were objectionable in many particulars. In the old method it was impossible to use a gang of punches,as they. could not be given the required pivotal move ment successfully on account of the unevenness of the blank surface causing lack of uniformity in the action of the different punches of the gang and resulting in imperfect work and breakage of the punches. Further than this the condition of the punch or punches affected the extent and time of the pivotally yielding action, as a newly ground tooth required but about half the movement to make In the old method, while the re-' a tooth, as that needed by a slightly worn punch, and thus this was particularly fatal to the use of a gang of punches for unless they all yielded at the same time so as to have movement in unison and an equal movement the result would be disastrous, and in fact these objections have been so serious that practically it has been impossible to use a gang of punches in theformation of teeth by Y the old method. These objections have been attended with serious results too in the use of a single punch, as the Wear upon thepunch was material great care in the grinding of the punches was necessary and even then the peculiar movement of the end of the punch rendered it liable to break at any time. By the present improvement I render unnecessary the use of the pivotally yielding punch holder and thus obviate the necessity for the peculiar movement of the punch which materially lessens the wear, renders it possible to use a simple form of punch which is easily made; obviates danger of breakage and enables me to use a gang with perfect results for the reason that the movement of the gang is uniform and positive and simply penetrates the metal on a straight line to form the teeth.

In the accompanying drawings: Figure 1 represents a front elevation of the machine partly in section. Fig. 2 is a sectional view of the same a quarter turned on the line ww, Fig. 1, showing a blank partially operated upon. Fig. 3 is a section on line yz of Fig. 1. Figs. 4 and 5 are detail views of the table for the blank. Figs. 6 and 7 show forms of gang punches. Fig. 8 is a detail view of the blank and punch made on a larger scale than Figs. 1 and 2.

' A represents the frame work which incloses the reciprocating frame B, which as shown in Fig.3, is guided in its up and down movement in the said frame A by means of ways. The frame A isarched at its upper end as, at b and bearings are formed for a shaft 0 carrying a balance wheel 1 and band wheels 52.

A cam D is centrally arranged on the shaft, the cam and shaft moving in the direction of the arrow: The frame B is depressed by the high part-of the cam to give the punching action and as soon as the shoulder of the cam has IOO [O or gang may be securely held by a set screw or other suitable means.

As the blanks are of varying thickness and as it is desirable to have theteeth of uniform height I have aimed to provide a construction of apparatus which will cause the teeth to be made uniform without regard to the irregularity of the thickness of the metal of the blank and this is attained by providing a definite determined movement of the punch by the action of the cam in relation to the thickness of the blanks and the amount of resistance offered. Thus in the thinner portions, the full movement of the punch is permitted and makes a tooth of the determined height while in the thicker portions the punch will penetrate the metal sulliciently to make a tooth of the same height but beyond this by reason of the increased resistance the movement imparted by the cam will be absorbed 0 by a spring interposed between the punch and the source of power which is adjusted to act at a certain resistance, while without some means of taking up this surplus move ment it is apparent that in the thicker por- 5 tions of the blank, teeth of greater height would be formed and the teeth would thus vary according to the variations in the thick ness of the blank. In carrying out this part of the invention I place within the cylinder 0 O a coiled spring and above the spring I place a disk Zthreaded upon the stem m which is swiveled at its upper end in the frame B. It will be seen that the blow delivered by the cam D upon the frame B is transmitted to 5 the tool through the stem m and its disk and the spring k and cylinder 0, but the spring is of such tension as to be unyielding in its action, except under the conditions stated.

In order to adjust the tension of the spring 70, I spline a ratchet lever it upon the stem m,

which is provided with a feather 0, the lever being held between the projections 19, extending from the frame. By the turning of this lever the tension of the spring may be increased or diminished by reason of the fact upwardly to diminish its power.

that the screw threaded end of the stem engages the disk Z, and in the rotation of the stem this disk is either moved downwardly against the spring to increase its tension or In order to prevent any change in the position of the cylinder 0 and the frame B by reason of such adjustment of the spring I form a stop to prevent the upward movement of the frame by means of the shoulders 8, bearing against the lower edge of the cylinder C.

In order to very quickly throw the punch in Figs. 2 and 8.

out of operation without stopping the rest of the machinery I provide a slide 25 on the upper end of the frame E which has ahandle u, and by means of this handle the slide may be withdrawn from under the cam and thus rotation of the cam will be efiected withoutaction upon the frame B. In order to regulate the force of the blow I move the slide beneath the cam so as to receive a full or partial action therefrom.

As I have before stated, I have found that by increasing the angle of inclination at which the table supporting the blank is held relatively to the line of the punch, the pivotally yielding movement of the punch is not required and the punch or gang may be rlgidly held in the end of the tool support and descend positively in a straight line upon the blank. The approximate inclination is shown This change in the inclination and in the method of raising the tooth necessitates a change in the punch, as the action is that of a direct punch instead of a combined punch and lift as heretofore and enables me to use a punch of simple form. This is shown in Fig. 8 and in gang form 111 i Figs. 6 and 7. The rear line of the punch is i centrally of the body and the side walls extend at right angles to each other toward the front, the shape of the punch in section be- 1 ing approximately square or diamond shaped.

The lower end is cut on a slant the lowest point being directly at the center of the extremity of the rear central line and the slant is upward from this line to the front. In Figs. 6 and 7 I show two forms of gang punches. W'hile a series of single punches may be used together, they are so small and require to be so accurately adj ustcd in relation to each other, that I find a great advantage in making the gang in one piece, as they can thus be handled as a single punch and sharpened as a single punch requiring no in.- dependent adjustment. The lower part or rear of the punch is the same, whether the punch be single, or in a gang or be made out of a single piece or fixed to a single piece. In both, the lower and rear side of the punch is formed with the sloping or inclined walls meeting at a central edge, which forms with the slant or bevel at the end, a sharp point.

In Fig. 6 the rear working face is shown at a formed with a strengthening piece b'serving also as the holding shank, the end being cut on a slant from the rear upwardly to the front, leaving a series of projecting punch points 0. Or the blank b may be made with the projections a on each face as in Fig. 7. The inclined table 4 supports a holder 5 for the blank, and this holder is moved downwardly step by step equal to the distance between the rows of teeth by means of a feed movement, consisting of the screw 6 turned by pawl and ratchet mechanism 7 operated from the source of power and this screw is engaged by a threaded lever 8 connected to the holder 5. The holderis moved downward face and in this recess against the pressure of, a spring or weight 9 which returns the nate lateral rows in alignment and I provide for the shifting of the blank to eficct this. The blank 10 is secured to a channeled plate 11 which in turn is held within a second channeled plate 12 which is within the holder proper. The holder has one side open and This is closed by a projection 13 from the table, which projection is recessed on its inner is inserted a plate 14 having a toothed or serrated face. The plate 12 is kept pressed against the projecting wall 13 of the table by springs 15 between it and the wall 16 of the table. The right hand side of the plate 12 has projecting V shaped pieces 17 fitting the likeserrations in the inserted piece and the action of the feed movement forcing the holder downward 'stepby step,

, this movement being equal to one half the distance between the apexes of the teeth on the inserted piece, moves the V shaped pieces 17 over the teeth of the inserted piece which shifts the plate 12 and the blank carried thereby to the left and the apex of the piece 17 bears'on the apex of one of the teeth of the inserted piece. A punching operation immediately follows while the blank is thus held and as soon as the punch is withdrawn the feed operates and the springs force the V shaped pieces down into the notch after which another punching operation follows and so on, the table 12 being thus shifted back and forth after each feed of the table so that the teeth punched alternate in position. In order to vary the amount of this shifting movement the inserted piece may be made removable and interchangeable pieces provided with finer or coarser teeth or serrations. A handle 18 is provided to throw back the plate 12 when it is desired to change the inserted piece.

While I have shown the table inclined and the punch arranged vertically the table may be horizontal and the punch inclined without departing from the spirit of my invention. This would still maintain the relative positions of punch and blank as shown in Fig. 8. This figure also illustrates the arrangement and movement of the punch or gang of punches as above explained. The punch, or

gang of punches, moves always in a right line and maintains the sameangle throughout its movement in relation to the blank. The bottom of the cavity from which the metal is taken to form a tooth, is shaped by the rear or under side of the punch; while the bevel forms the face of the tooth and bears against the metal, maintaining always the same relation to the metal, as it pushes it back.

cross-section, this being The edge underneath with its sloping sides forms'a corresponding groove V-shaped in the tooth cavity. The metal is lifted up out of this cavity, simwhen the lever 8 is ply by the wedging action of the bevel face of the punch and by its direct movement. Thus a definite and certain plain face of a tooth is formed, invariably uniform and without any possible curltor turned edge.

When a single punch is used, it will henndertood that it is to be used in a machine, such as heretofore known, and in use, 1n which the punch is shifted laterally step by step to form a lateral row of teeth.

When the gang is used, it is used 1n a machine such as that above described, in wh ch the gang is shifted laterally after formlng one row, in order to form the other with its teeth opposite the spaces between the teeth of the first row.

I claim as my invention- 1. In combination with the bed of a rasp punching machine,a punch holder arranged to reciprocate at an angle to said bed, and a punch rigidly fixedin said holder, thereby reciprocating in a direct line and at a certain angle to the bed, the said punch being'formed with plain inclined faces on its under side, meeting in a central point forming edge, arranged to form the bottom of the tooth cavity, and with a beveled end slopingfrom the point below, and varranged to push up the metal and form the face of the tooth, substantially as described.

f2. In'combination with the bed of a rasp punching machine, a punch holder arranged to reciprocate at an angle to said bed, a gang punch each punch of the gang being formed with plain inclined faces on its under side, meeting in a central point forming edge and arranged to form the bottom of the tooth cavity and all having beveled ends sloping at about the same angle, from the points below, and arranged toform the face of the teeth,-

said gang being set in the holder to reciprocate in a direct line in relation to the bed, and mechanism for changing laterally the lIO relative position of the punch gang and the bed, substantially as described.

3. In combination, with the vertically movable frame B, means for applying pressure thereto, a tool carried by a barrel 0, receiving movement from said frame B, and a spring between said barrel and, frame, substantially as described.

4. In combination, with the vertically movable frame B, means for applying pressure thereto, a barrel 0, a tool-carried thereby, a spring between said barrel and frame and means for adjusting the spring, substantially as described.

5. In combination with a tool, the frame,

means for applying downward pressure to said frame, a spring between said tool and frame and springs between the hammer frame and main frame fortlifting said hammer frame after its downward movement, substantially as described.

6. In combination witha punch and niechanism for operating it, a stationary table for supporting the blank, a. longitudinally mov able holderbetween the blank and table, the for shifting the plate 12, substantially as de :0 blank heinq movably supported Within the scribed.

holder, and means for shifting the blank lat- In testimony whereof Iaffix my signature in erally within the holder, substantially as depresence of two witnesses.

5 scribed. I l

7. In combination with a gang punch and JOHN S1 OKES' mechanism for operating it, a table, a longi- \Vitnesses: tudinally movable l1older,an(1 a laterally mov- WM. MCDERMOTT,

able plate 12 supporting the blank, and means JOSEPH MCDERMOTT. 

